Article excerpt

Since the volcano awoke on the Caribbean isle of Montserrat
two years ago, it has become a showcase for volcanologists. Their
gas sniffers, seismometers, and other gear have kept islanders as
alert to their restless mountain as they would be to an approaching
hurricane.

Yet one aspect of their geophysical prowess disappoints
Michael Sheridan: Their forecasts, he says, haven't kept up with
the volcano's growing destructive potential.

A volcano scientist with the State University of New York at
Buffalo, Dr. Sheridan notes that it must be "disturbing" to look at
a map designating your area as safe only to learn it isn't safe
anymore.

At that point, he adds, people in the area may not believe
the revised warning. He doesn't blame the Montserrat Volcano
Observatory team for the confusion. It didn't have crucial
background data needed to assess what it's dealing with.

Sheridan explains that "the real problem" in volcano
forecasting "is to establish a base-line knowledge of what a
volcano is like before it shows signs of danger." Then monitors can
pick up on small surface deformations, gas emissions, faint
underground rumbles, and other subtle signs of a volcano's
awakening years before there's obvious action. If they come in cold
when eruption seems imminent, they are handicapped in figuring out
what is going on, Sheridan says.

Amassing knowledge

Developing that base-line knowledge for hundreds of volcanoes
around the world is the challenge volcanologists face as they enter
the 21st century. Members of the Montserrat volcano team pointed
this out in the journal Science last April. They noted that "many
of the world's most dangerous volcanoes are still poorly
understood," adding that "this lack of knowledge represents the
most pressing problem in reducing volcanic risk in a global
context."

There's more to that risk than a rain of hot rocks or flaming
rivers of lava. Ash clouds from even mild eruptions can endanger
aircraft. A "sleeping" volcano like Mt. Rainier in Washington State
may be quietly melting its snow cap from below. The melt water then
rots the underlying rock until it can suddenly give way, releasing
a devastating mudflow. For Rainier, that would put much of Seattle
at risk.

As a step toward getting the needed knowledge, the
International Association of Volcanology and Chemistry of the
Earth's Interior has designated 15 active mountains as "Decade
volcanoes." (See box, below.) That marks them for intensive study
as part of the United Nations International Decade for Natural
Disaster Reduction program. They are not necessarily the most
dangerous. There's no international money for the volcano program.
Its sponsors hope that a Decade designation will give that volcano
a certain priority in a nation's research funding.

That's happening in the United States. Marianne Guffanti,
coordinator of the US Geological Survey (USGS) volcano hazards
program in Reston, Va., says the survey now monitors 37 of 65
suspect volcanoes in the US (for more information: volcanoes. …